FHIR Identifier Data Type (R5)

Identifier is a business identifier such as an MRN, NPI or order number. Element table, example JSON and FHIRPath for FHIR R5.

FHIR Identifier Data Type (R5) — part of the free FHIR Toolbox library.
Runs entirely in your browser: your FHIR data is never uploaded to a server.

Overview

Identifier is a business identifier such as an MRN, NPI or order number. The system namespaces the value, so the pair (system, value) is what makes it unique.

Elements

Element	Type	Cardinality	Description
Identifier.use	code	0..1	usual \| official \| temp \| secondary \| old (If known)
Identifier.type	CodeableConcept	0..1	Description of identifier
Identifier.system	uri	0..1	The namespace for the identifier value
Identifier.value	string	0..1	The value that is unique
Identifier.period	Period	0..1	Time period when id is/was valid for use
Identifier.assigner	Reference	0..1	Organization that issued id (may be just text)

Example JSON (R5)

{
  "use": "official",
  "type": {
    "coding": [
      {
        "system": "http://terminology.hl7.org/CodeSystem/v2-0203",
        "code": "MR"
      }
    ]
  },
  "system": "http://hospital.example.org/mrn",
  "value": "12345"
}

FHIRPath

Patient.identifier.where(system='http://hospital.example.org/mrn').value — Value for one system
Patient.identifier.system — All identifier systems

FHIR Toolbox is a free, privacy-first collection of HL7 FHIR utilities by Omindra Labs. Every tool performs zero-server processing — your health data never leaves your device.